/*
 * Copyright (c) 2004-2022, University of Oslo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * Neither the name of the HISP project nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.hisp.dhis.node;

import static com.google.common.base.Preconditions.checkNotNull;

import java.util.ArrayList;
import java.util.List;

/**
 * Simple linear pipeline that run transformers sequentially.
 *
 * @author Morten Olav Hansen <mortenoh@gmail.com>
 */
public class LinearNodePipeline implements NodePipeline {
  private class NodeTransformerWithArgs {
    NodeTransformer transformer;

    List<String> arguments;

    NodeTransformerWithArgs(NodeTransformer transformer, List<String> arguments) {
      this.transformer = transformer;
      this.arguments = arguments;
    }

    Node transform(Node node) {
      return transformer.transform(node, arguments);
    }
  }

  private List<NodeTransformerWithArgs> nodeTransformers = new ArrayList<>();

  @Override
  public Node process(Node node) {
    for (NodeTransformerWithArgs nodeTransformer : nodeTransformers) {
      node = nodeTransformer.transform(node);

      if (node == null) {
        return null;
      }
    }

    return node;
  }

  public void addTransformer(NodeTransformer nodeTransformer) {
    nodeTransformers.add(
        new NodeTransformerWithArgs(checkNotNull(nodeTransformer), new ArrayList<>()));
  }

  public void addTransformer(NodeTransformer nodeTransformer, List<String> arguments) {
    nodeTransformers.add(new NodeTransformerWithArgs(checkNotNull(nodeTransformer), arguments));
  }
}
